Modafinil Dosage Guide | Uses, Indications, and Microdosing

Modafinil Dosage

Curious about the perfect Modafinil dosage that provides all the upsides of cognitive enhancement without any downside?

You're not alone. Many smart drug users have been asking us about the optimal dosage of Modafinil they can feasibly use over long periods of time.

Which leaves several questions answered…

Is it fruitful to start Modafinil dosing to the highest levels until one begins feeling discomfort? Would a user instead be better off with Modafinil microdosing and gradually working their way up to higher dosages?

Or is there a Modafinil dosage that hits the sweet spot for any nootropic user?

This article will set the record straight on how to start thinking about the right Modafinil dose for your productivity needs.

Disclaimer: The contents of are for informational and educational purposes only. We do not provide legal advice. Likewise, we do not provide medical advice, diagnosis, or treatment. Please consult your physician prior to consuming Modafinil or related nootropics. Your access to is subject to our full Disclaimer and Terms of Use.

What Is Modafinil?

Before we can discuss the ideal dosage of Modafinil, let's briefly cover what Modafinil is and why so many people seemingly swear by the smart drug.

Modafinil (brand name: Provigil) is an FDA-approved wakefulness drug that is used to treat narcolepsy, shift work sleep disorder, and obstructive sleep apnea. It does not directly treat the conditions themselves, but rather the excessive daytime sleepiness commonly associated with all three conditions.

The precise mechanism of action is not fully understood, but Modafinil is believed to increase the production of several neurotransmitters such as serotonin, histamine, norepinephrine, glutamate, and dopamine [1].

Eventually, Modafinil found its way towards being used off-label as a cognitive enhancer in the early 2000s.

Healthy individuals who did not suffer from sleep deprivation discovered that Modafinil gave them a significant boost in mental performance [2]:

“Pharmaceutical intervention in the sleep–wake cycle was represented as a way to reduce time spent sleeping, a method of potentially ‘eliminating sleep’ altogether and a tool to enhance one's cognitive abilities.

Modafinil was tipped as the next ‘wonder drug’ to hit the UK with claims made that it could become the ‘pharmaceutical equivalent of the electric light bulb’ by ‘extending the waking day.’”

Commonly, Modafinil is used by people in brutally competitive industries as a potential means of getting ahead of the competition [2].

Generic Modafinil

Modafinil Side Effects and Safety Concerns

But are there any side effects associated with taking a typical Modafinil dosage? For a smart drug — or any drug — to be worthwhile, the benefits need to outweigh the downsides significantly.

Fortunately, Modafinil appears to have one of the best safety profiles of any pharmaceutical drug in its class that has ever been developed. The common side effects of Modafinil include [3]:

  • Headache
  • Nausea
  • Anxiety
  • Difficulty sleeping
  • Dizziness
  • Dry mouth/eyes

The good news is that these side effects rarely occur with proper dosage, and when they do, they are mild in nature. Furthermore, intervention is usually straightforward and tends to work immediately (e.g., for dehydration, one simply has to drink more water than usual).

In a variety of settings, Modafinil is the preferred “drug of choice” over traditional stimulants as it possesses fewer side effects [4]:

“Modafinil is less related to side effects such as excess locomotor activities, anxiety, jitteriness, or rebound effects than the traditional stimulants…[Modafinil] is also more effective than amphetamine”

Of course, all of this assumes you are dosing Modafinil properly and not intentionally abusing the drug by using it too much (and too frequently).

Modafinil Dosage Guide | The Basics

Everyone will ultimately go through their own individual “Modafinil dosing” journey, but the end goal remains the same:

Find the perfect Modafinil dosage that allows one to achieve the highest level of cognitive enhancement for the desired period of time while minimizing the possibility of experiencing unwanted side effects.

But this brings up two main questions:

  1. What Modafinil dosage should I start at?
  2. What criteria should I use to determine if I increase or decrease my dosage of Modafinil?

Of course, we’re not authorized to dispense medical advice, but we can speak from our experience — so take this with a grain of salt.

For the first question, good results have been reported starting at 100mg of Modafinil. We take it early in the morning, no later than 9am, so as to prevent Modafinil from interfering with our normal sleep schedules.

(NOTE: It’s important to avoid taking any drugs other than Modafinil, or making significant changes to your usual routine. Otherwise, this could compromise  results [5]).

We’ll typically do this 2-3 times throughout the week, with each dose at least 48 hours apart from each other. We find it important to gauge how you feel while on Modafinil and whether you are experiencing any side effects.

After the initial 100mg, when we felt we weren’t overstimulated and did not notice any side effects, we would bump the dose up by 25mg for the next week. We would then rinse and repeat the evaluation process, re-evaluating on a weekly basis.

However, when we did start experiencing side effects and/or feeling overstimulated, we would lower the dose by 25mg for the next week. Again, we would take stock of how the lowered Modafinil dosage had affected our well-being and cognition.

The Neuroscience Education Institute provides dosing tips for individuals who do suffer from excessive sleepiness and fatigue [6]:

For sleepiness, more may be more : higher doses (200–800mg/day) may be better than lower doses (50–200mg/day) in patients with daytime sleepiness in sleep disorders

For problems concentrating and fatigue, less may be more : lower doses (50–200mg/ day) may be paradoxically better than higher doses (200–800mg/day) in some patients.

As you can see, different users may ultimately require different doses of Modafinil to find the right balance.

Standard Prescription Modafinil Dose?

The Modafinil dosage that might be right for you will not necessarily be the same as the drug’s standard prescription dose.

According to the official FDA product monograph, Modafinil is prescribed at 200mg per day for all of its approved indications, either in the morning or one hour before starting a work shift [7]. Here's why:

“Doses up to 400mg/day, given as a single dose, have been well tolerated, but there is no consistent evidence that this dose confers additional benefit beyond that of the 200mg dose.”

Modafinil comes in either 100mg or 200mg tablets, as some patients find a lower dosage of Modafinil is as much as they can handle without feeling overwhelmed.

Overall, most of the literature and studies have shown 200mg to be the ideal Modafinil dosage for most users — especially individuals using the pharmaceutical drug as a nootropic.

However, keep in mind that 400mg of Modafinil is considered a maximal dosage for physicians. For some individuals, taking such high quantities of Modafinil may lead to experiencing a greater severity of side effects like nervousness and nausea [8].

Develop Your Personal Dosing Guidelines | 50-400mg

If you're curious about Modafinil or interested in tweaking your dosage, here are a few things we have noted when trying different dosing protocols:

Modafinil Dosage of 50mg

For us, the increase in cognitive enhancement was mild and only lasted 2-3 hours.

We find that taking 50mg of Modafinil for 4-6 days a week is feasible, versus the 2-3 days per week we have to abide by if taking 100-200mg of Modafinil at a time.

Also, no side effects were reported whatsoever at this dosage of Modafinil.

With that said, we would think most users would not benefit from starting at this low a dosage, unless there’s a history of being overly sensitive to stimulants.

One Reddit user's testimonial best describes individuals who do very well on a smaller dosage of Modafinil [9]:

“50mg works the best for me too, by far. With 100-200mg, I'd feel overstimulated for a couple of hours, get a headache, then crash and feel like crap for the rest of the day.

50mg followed by a coffee or two, then lots of water, is absolutely perfect to keep me going for the day, then still sleep well at the usual time.”

Modafinil Dosage of 100mg

When we need increased focus during a typical “9-5” workday, then a 100mg Modafinil dosage is probably our ideal starting point.

This seems in line with previously published studies, where 100mg of Modafinil was sufficient for most patients to notice significant differences in cognitive functioning [10].

Due to Modafinil's half-life of 12-15 hours [11], we notice that the boost in cognitive enhancement starts to wear off around 7-8 hours after taking 100mg.

A few team members do prefer splitting up their daily Modafinil dosage of 100mg into two separate doses – 50mg at 7-8am, and the remaining 50mg at 12-1pm.

If you take this dosage of Modafinil and don't notice improved focus, keep reading.

Modafinil Dosage of 200mg

This is the standard dose taken by most smart drug users who are seriously using Modafinil to become more energetic and focused for the majority of the working day.

As mentioned before, it is also the most “well-researched” dosage of Modafinil and it is officially recommended in Modafinil's product monograph for patients who are prescribed the drug [12]:

“The recommended starting daily dose is 200mg. The total daily dose may be taken as a single dose in the morning or as two doses, one in the morning and one at noon, according to physician assessment of the patient and the patient's response.”

At 200mg of Modafinil, we find that most users feel all the desired cognitive effects with little to no side effects.

We find that most Modafinil users in fact do well with this dose at 1-3 days per week. There doesn’t seem to be much clinical evidence to suggest more than 200mg of Modafinil adds additional benefits, or that splitting your Modafinil dosage into two 100mg doses makes any real difference.

Modafinil Dosage of 300mg

Unless we absolutely need an additional 1-2 hours of focus, or plan on staying up for more than 24 hours, we would not take a dose of 300mg of Modafinil.

Even when we’ve taken this dose early in the morning, we found extreme difficulty with falling asleep before 3-4am, and woke up feeling “slightly hungover” the next morning.

This Modafinil dosage has not been extensively studied in the literature, but some of the studies make several suggestions that are in line with observations.

In one study comparing different levels of Modafinil dosing to 100mg of caffeine, using 300mg of Modafinil to power through sleep deprivation lowered performance the very next day [13]:

“Enhanced performance with modafinil during overnight work varied with dose (200mg > 100mg; 300, 400mg > 200, 100mg, caffeine).

However, in the study of next-day performance, the enhancement was attenuated at the highest dose (300mg) by the greater disturbance of prior sleep.”

However, in another study dosing Modafinil in French military soldiers deprived of sleep for 64 hours, 300mg of Modafinil was the only dose that allowed them to maintain the same level of cognitive performance relative to baseline levels [14].

If you decide to use this dosage of Modafinil, consider splitting the daily dose into two smaller doses: 150mg in the early morning, and 150mg right after eating lunch.

Modafinil Dosage of 400mg

For the purpose of cognitive enhancement, we have found that using this dose has not resulted in any performance improvement over our 300mg protocol, or even a one-time 200mg dose. 

Even physicians are recommended not to go any higher than 400mg of Modafinil a day for patients suffering from shift work sleep disorder, narcolepsy, or sleep apnea [15].

We surmise there may only be a few instances where 400mg of Modafinil may be required for enhancing cognition:

  • An unusual metabolism whereby Modafinil is eliminated at a faster rate
  • Individuals who have developed a heavy tolerance to Modafinil (to which we would rather advise an extended break from Modafinil) 
  • Smart drug users who are extremely large in size 

We actually noted experiencing a higher frequency and severity of side effects at this high dose of Modafinil — brain fog, chronic fatigue, difficulty concentrating, lower energy levels, and so on.

Moreover, the positive aspects of Modafinil tend to quickly wear out, possibly leading to overconfidence in your own mental capabilities [16]:

“A single dose of modafinil seems to have a cognitive enhancing effect in cases of moderate sleep deprivation. In repeated doses it does not seem to boost cognitive performance over a longer period of sleep deprivation, but only maintains wakefulness.”

In summation, experience tells us that 400mg of Modafinil should be avoided unless you have a clinical need for it.

Microdosing Modafinil

“Modafinil microdosing” can be defined as taking 1/5th to 1/10th of the standard Modafinil dosage. In practice, 50mg of Modafinil or less would be considered a microdose of Modafinil.

Many people who feel that a Modafinil dosage of 100mg is “too much” may find much smaller doses to be more tolerable. They can still experience the positive aspects of Modafinil without experiencing any side effects whatsoever.

In a Reddit forum discussing the benefits of microdosing Modafinil, one user chimed in with their success in taking 12.5mg of Modafinil per day [17]:

“With the microdoses, there are also no lingering after effects, and consecutive day uses tend to be more effective.

Bottom line, my personal experience is this stuff has almost saved me by allowing me to work continuously and productively with focus, for an extended calendar length of time”

Microdosing Modafinil may also be useful if you suffer from liver issues or happen to be 65 years or older [18].

If you are looking to start with extremely small doses of Modafinil and work your way up towards a larger microdose, this proposed schedule from one smart drug user helped them find 70mg of Modafinil per day to be their ideal dose [19]:

  • Days 1-3: Take 25mg of Modafinil at the same time each day
  • Days 4-6: Three-day break
  • Days 7-9: Take 50mg of Modafinil at the same time each day
  • Days 10-12: Three-day break

You would repeat the “three day on, three day off” cycle with progressively larger doses until you find your best Modafinil dosage.

Lethal Dosage?

If you take a look at the official medication guide for Modafinil, you will find the following blurb under the “Overdosage” section [20]:

“In clinical trials, a total of 151 protocol-specified doses ranging from 1000 to 1600mg/day (5 to 8 times the recommended daily dose of 200mg) have been administered to 32 subjects, including 13 subjects who received doses of 1000 or 1200mg/day for 7 to 21 consecutive days.

In addition, several intentional acute overdoses occurred; the two largest being 4500mg and 4000mg taken by two subjects participating in foreign depression studies. None of these study subjects experienced any unexpected or life-threatening effects”

The side effects associated with overdosing on Modafinil usually include chest pain, higher blood pressure, irregular heartbeat, hallucination, excessive agitation, and overall restlessness.

To put all this in context: The “LD50” of Modafinil — the dose of a drug required to kill 50% of all test subjects — in rodents taking it orally is 1.0-1.25 g/kg [21]. So for a 70 kg (~155lb) male, they would need to take 75 grams of Modafinil for the smart drug to be considered deadly!

Nobody has ever been reported to exceed 12 grams of Modafinil in a single day.

Modafinil Dosing | The Verdict

You’re now equipped with the information you need on determining the Modafinil dosage for your nootropic needs.

Research studies and observations are straightforward and simple, but here's a very quick recap of what we discussed in this article:

Users who don’t have substance abuse issues and are new to smart drugs appear better off on a 100mg dosage of Modafinil and gradually working their way up to 200mg. When using this protocol, many have reported increased cognition, focus, and productivity — without many of the negative side effects.

On the other hand, users who are overly sensitive to stimulants and want to take Modafinil more frequently during the week seem better off on a daily microdose of 50mg or less.


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Medically Review by:
Diana Rangaves, PharmD, RPh

Table of Contents

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